COM Query String Input

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COM Query String Input

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The Com Query String input node allows receiving ASCII feedback messages from COM devices over a local COM Port connection. The COM Port connection needs to be enabled in the Connection Manager.
This input node will output any incoming packet as Text Only, Numeric Only or mixed string.


Node Properties:

COM Connection ID:
Enter the ID of the COM Port connection.

Query String:
Enter the query string that you want to send to the specified COM Device.

Enter the time interval in ms in which the query string will be send to the COM Device.
If you want to query the device manually (e.g. by pressing a Custom Script Button using the command “WDNodeSetParam,'NodeID','ParamID','Value'”), please set the Interval Time to 0 ms.

The response of the COM Device will be displayed here. Please note that the responding device needs to send a "carriage return", a "line feed" or an "end of text" at the end of its message. This can be done in ASCII, decimal or hexadecimal language.
- carriage return is either [CR] or [d13] or [h0D]
- line feed is either [LF] or [d3] or [h3]
- end of text is either [ETX] or [d10] or [h0A]

The Timeout gives you feedback about the connection status. If Timeout is “0”, there is no communication with the specified COM Device. If Timeout is “1” the communication works.
Confirm your settings by pressing OK or Apply.

The Node generates the following output:

- COM Query String Response,

- COM Query String Text Only,

- COM Query String Numeric Only

- COM Query String Timeout.